Generally, a refrigerator includes a refrigerating chamber for refrigerating and storing food and a freezing chamber for freezing and storing food. At this point, an ice maker for producing ice is installed in the freezing chamber or the refrigerating chamber.
FIG. 1 is a bottom view of the existing ice maker for a refrigerator.
Referring to FIG. 1, an ice maker 10 includes a heater 27 that is on a lower surface of an ice tray 11. When the ice-making is completed, a heater 27 slightly melts ice firmly coupled to an inner side of the ice tray 11, thereby serving to separate ice. The heater 27 mainly uses a U-shaped sheath heater.
Here, since the heater 27 is formed to be line contact in a U-letter shape under the ice tray 11, and therefore an area in which the heater 27 directly contacts the ice tray 11 decreases, such that heat transfer efficiency is degraded. It takes a lot of time and power to melt ice in the ice tray 11 by transferring heat to a portion not directly contacting the heater 27. At this point, since the ice tray 11 is excessively heated by the heater 27, it takes a lot of time to again cool the ice tray 11 to the ice-making temperature in the ice-making cycle after the ice separation, such that the ice-making time may be long.